Sinus arrest

Lidocaine Dizziness, sedation, slurred speech, blurred vision, paresthesia, muscle twitching, confusion, nausea, vomiting, seizures, psychosis, sinus arrest, aggravation of underlying conduction disturbances... 

Sick sinus syndrome Use only with extreme caution the drug may cause sinus bradycardia, sinus pause, or sinus arrest. The frequency probably increases with higher trough plasma levels. 

Hypertrophic cardiomyopathy (IHSS) Serious adverse effects were seen in 120 patients with IHSS (especially with pulmonary artery wedge pressure more than 20 mm Hg and left ventricular outflow obstruction) who received oral verapamil at doses up to 720 mg/day. Sinus bradycardia occurred in 11%, second-degree AV block in 4% and sinus arrest in 2%. 

Overdosage produces vomiting, lethargy, syncope, hypotension, conduction disturbances, exacerbation of CHF, MI, and sinus arrest. 

Sick sinus syndrome Severe bradycardia (<50 beats/min) periods of sinus arrest... 

The most commonly reported cardiac signs of toxicity are dysrhythmias, such as ventricular ectopic depolarization, second- and third-degree heart block, junctional tachycardia, atrial tachycardia with block, ventricular tachycardia, sinoatrial block, and sinus arrest. 

Verapamil s cardiotoxic effects are dose-related and usually avoidable. A common error has been to administer intravenous verapamil to a patient with ventricular tachycardia misdiagnosed as supraventricular tachycardia. In this setting, hypotension and ventricular fibrillation can occur. Verapamil s negative inotropic effects may limit its clinical usefulness in diseased hearts (see Chapter 12 Vasodilators the Treatment of Angina Pectoris). Verapamil can lead to atrioventricular block when used in large doses or in patients with atrio-ventricular nodal disease. This block can be treated with atropine and -receptor stimulants. In patients with sinus node disease, verapamil can precipitate sinus arrest. 

Adenosine 20-100 xg Have the same indications as sodium nitroprusside Can cause sinus arrest/AV block when high doses are used, especially in the RCA (an effect which is reversible within seconds)... 

A very uncommon adverse effect involves sinus node dysfunction (extreme bradycardia, sinus arrest, sinoatrial block), which can be associated with syncopal episodes, perhaps due to hypothyroidism (119,120). In such cases, lithium must either be withdrawn or continued in the presence of a pacemaker. At therapeutic concentrations, other cardiac conduction disturbances have been reported, sometimes in conjunction with hypercalcemia (121), but are uncommon. 

Two reviews of the cardiac effects of psychotropic drugs briefly mentioned lithium and dysrhythmias, with a focus on sinus node dysfunction (122,123), reports of which, as manifested by bradycardia, sinoatrial block, and sinus arrest, continue to accumulate in association with both toxic (124) and therapeutic (125,126) serum lithium concentrations. The rhythm disturbance normalized in some cases when lithium was stopped (124,126), persisted despite discontinuation... 

Bradycardia often occurs with the combination of a potent short-acting opioid with suxamethonium during induction of anesthesia, and alfentanil has been reported to have caused sinus arrest in three patients (SEDA-17,79) (3). 

Ananthanarayan C. Sinus arrest after alfentanil and suxamethonium. Anaesthesia 1989 44(7) 614. 

In 72 patients with paroxysmal atrial fibrillation randomized to either amiodarone 30 mg/kg or placebo, those who received amiodarone converted to sinus rhythm more often than those given placebo (22). The respective conversion rates were about 50 and 20% at 8 hours, and 87 and 35% after 24 hours. The time to conversion in patients who converted did not differ. One patient developed slow atrial fibrillation (35/minute) with a blood pressure of 75/ 55 mmHg. Three other patients who received amiodarone had diarrhea and one had nausea. In the control group two patients had headache, one had diarrhea, one had nausea, and two had episodes of sinus arrest associated with syncope during conversion to sinus rhythm the last of these was thought to have sick sinus syndrome. 

Sinus arrest with hypotension has been reported in a patient with a congestive cardiomyopathy when diltiazem was added to amiodarone (255). 

Lee TH, Friedman PL, Goldman L, Stone PH, Antman EM. Sinus arrest and hypotension with combined amiodarone-dUtiazem therapy. Am Heart J 1985 109(1) 163. ... 

Patients with impaired function of the sinus node or impaired atrioventricular conduction can develop sinus bradycardia, sinus arrest, heart block, hypotension and shock, and even asystole, with verapamil (139) or diltiazem. These drugs should not be given to patients with aberrant conduction pathways associated with broad-complex tachydysrhythmias, and they can cause severe conduction disturbances in hypertrophic cardiomyopathy. 

Four additional cases of carbamazepine-induced sinus node dysfunction (n = 3) and atrioventricular block (n = 1) were described in elderly Japanese women taking 200-600 mg/day. In two of the three patients rechallenged, sinus arrest recurred within 48 hours (8). 

A death due to ventricular fibrillation after 50 mg and another due to sinus arrest after 100 mg have been reported (SED-12, 255) (17). Two cases of ventricular fibrillation and cardiopulmonary arrest occurred after local infiltration of lidocaine for cardiac catheterization (SEDA-21,136). 

Other cardiovascular effects include widening of the QRS complex, atrioventricular dissociation, heart block, sinus arrest, and cardiac arrest (23,24). 

In a 49-year-old otherwise healthy woman undergoing craniotomy for aneurysm clipping, inadvertent overdose with phenytoin (1500 mg) by rapid infusion caused intraoperative sinus arrest, which was managed successfully with standard resuscitative measures (5). 

Conduction disturbances are common with propafenone and can result in sinus bradycardia, sinoatrial block, sinus arrest, any degree of atrioventricular block, and right or left bundle-branch block (SEDA-10,151) (SEDA-15,179). 

Quinidine has also been incriminated in cases of sinoatrial block and sinus arrest, but it was not clearly established that quinidine was responsible (9,10). The anticholinergic effects of quinidine can increase the risk of dysrhythmias (11). 

Other isolated reports and preliminary studies have suggested a possible risk of life-threatening dysrhythmias, including sinus bradycardia or sinus arrest, asymptomatic but significant mean QT/QTc interval prolongation in 33 patients (over 500 msec in seven patients), and recurrent episodes of ventricular tachycardia or torsade de pointes in two patients (SEDA-21, 391) (SEDA-22, 390) (15,16). 

During repeated administration cardiovascular adverse effects are relatively uncommon. Increasing heart failure (14,15), worsening dysrhythmias (15,16), pericarditis (15,17,18), and sinus arrest with sinoatrial block (19) have all been reported. Tocainide can worsen ventricular tachycardia (20). 

Lidocaine CNS, seizures, psychosis, sinus arrest, aggravation of underlying conduction... 

Another reason for paroxysmal bradycardia and sinus arrest that is not due directly to sinus node dysfunction is carotid sinus hypersen-... 

Encainide, a class 1C antiarrhythmic agent, is available on a limited basis only to patients with life-threatening ventricular arrhythmias. Encainide slows conduction velocity, inhibits automaticity, and increases the ratio of the effective refractory period to action potential duration. It blocks the sodium channel of Purkinje fibers and the myocardium. Encainide is absorbed well, reaches peak plasma level in 30 to 90 minutes, becomes metabolized to 0-demethyl encainide (ODE) and 3-methoxy-O-demethyl encainide (MODE), which are active antiarrhythmic agents, and the metabolites are excreted by the kidneys. In renal impairment, the clearance of ODE and MODE is decreased, and hence the dosage should be reduced. Encainide may either worsen or create new arrhythmias, especially in electrolyte-imbalanced patients. Encainide is known to have caused sinus bradycardia, sinus pause, or sinus arrest (see also Eigure 84). 

Sotalol should be used cautiously in pregnant patients and patients with renal failure or diabetes mellitus. Sotalol should be used with extreme caution in patients with sick-sinus syndrome associated with symptomatic arrhythmias, because the drug can cause sinus bradycardia, sinus pauses, or sinus arrest. 

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